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Consiglio, A.

Publications and source records attributed to Consiglio, A..

8 recordsLinked to original sources

The two sides of resistance: aggressiveness and mitotic instability as the Achilles heel of Osimertinib-resistant NSCLC

Non-small cell lung cancer (NSCLC) represents majority of lung cancer cases and remains a leading cause of cancer mortality worldwide. Tumors carrying activating mutations in the epidermal growth factor receptor (EGFR) are highly sensitive to EGFR tyrosine kinase inhibitors (TKIs), with third-generation inhibitors such as Osimertinib now established as standard of care. However, acquired resistance to Osimertinib inevitably develops, involving both genetic and non-genetic mechanisms, the latter playing a major role in sustaining cellular plasticity and promoting tumor aggressiveness. Among regulators of adaptive programs, the Polycomb protein BMI1 has emerged as a key factor driving stemness, epithelial-to-mesenchymal transition (EMT), and therapy resistance in multiple cancers, yet its role in Osimertinib resistance remains poorly defined. Here, we show that Osimertinib-resistant H1975 cells, which display greater aggressiveness than their parental counterparts, are enriched in BMI1 target genes and mitotic cell-cycle pathways, establishing a dependency on microtubule dynamics and mitotic control. Functionally, BMI1 drives migration, invasiveness, and tumor progression in resistant cells. This mitotic dependency creates a therapeutic vulnerability that can be exploited with Unesbulin (PTC596), a BMI1 inhibitor that destabilizes microtubules and induces mitotic catastrophe, thereby effectively suppressing tumor growth in vitro and in vivo. Our findings establish BMI1 as a central mediator of Osimertinib resistance and provide a mechanistic and therapeutic rationale for targeting BMI1 and mitotic weaknesses in refractory EGFR-mutant NSCLC.

cancer biology↗

Astrocytic Ceruloplasmin Deficiency Triggers Iron Toxicity and Neurodegeneration in a LRRK2 Parkinson's Tri-Culture Model

Astrocytes and microglia carrying the LRRK2-G2019S mutation contribute to non-cell- autonomous dopaminergic neuron (DAn) degeneration in Parkinsons disease (PD), but the mechanisms underlying their interplay remain unclear. Here, we developed a novel induced pluripotent stem cell (iPSC)-derived tri-culture system comprising healthy DAn and either LRRK2-mutant or isogenic control iPSC-derived astrocytes and microglia. Using integrated functional assays and transcriptomic profiling, we found that mutant astrocytes adopt a hyperreactive state, driving microglial activation and subsequent DAn degeneration. Mechanistically, we identified a selective downregulation of ceruloplasmin (CP), a copper-dependent ferroxidase, in mutant astrocytes, leading to disrupted iron homeostasis with accumulation of Fe2+ and ROS. This iron dysregulation mediated both microglial reactivity and neurodegeneration. Notably, pharmacological restoration of CP re-established iron homeostasis, reduced microglial activation, and protected DAn from degeneration. Our findings uncover a novel astrocyte-microglia-neuron axis driving PD pathogenesis and showcase the power of our unique stem cell tri-culture platform for dissecting disease mechanisms and discovering therapeutic targets.

cell biology↗

α-Synuclein aggregates induce mitochondrial damage and trigger innate immunity to drive neuron-microglia communication

Tunneling nanotubes (TNTs) enable direct intercellular transfer of macromolecules, organelles, and pathogenic protein aggregates. While -synuclein (-Syn) aggregates are known to promote TNT formation, the underlying mechanisms remain poorly defined. Here, using human neuronal and microglial cell lines, as well as iPSC-derived dopaminergic neurons and microglia, we show that -Syn aggregates induce severe mitochondrial damage, leading to cytosolic release of mitochondrial DNA (mtDNA) and activation of the cGAS-STING-NF- {kappa}B-IRF3 pathway. This innate immune response drives actin cytoskeleton remodeling and the formation of TNT-like structures, promoting intercellular transfer of -Syn from neurons to microglia. Additionally, neuronal cells transfer damaged mitochondria to microglia, where they undergo lysosome-mediated degradation. Neuron-to-microglia communication under -Syn- induced stress also triggers a bystander inflammatory response in microglia, suggesting a neuroimmune activation. Our findings identify mitochondrial damage and STING-mediated inflammation as key drivers of TNT formation and -Syn propagation, highlighting new potential targets to modulate disease progression in Synucleinopathies.

cell biology↗

LRRK2-mutant microglia trigger dopaminergic neurodegeneration when activated by neuromelanin

Parkinsons disease (PD) is a progressive, incurable neurodegenerative disorder characterized by the loss of neuromelanin (NM)-containing dopamine neurons (DAn) in the substantia nigra of the midbrain. Non-neuronal cells are increasingly recognized as contributors to PD. We generated human microglia-like cells (hMG) from induced pluripotent stem cells (iPSC) derived from patients with LRRK2 PD-causing mutations, gene-corrected isogenic controls, and healthy donors. While neither genotype induced neurodegeneration in healthy DAn, LRRK2 hMG become hyperreactive to LPS stimulation, exhibiting increased cytokine expression, reactive oxygen species, and phagocytosis. When exposed to NM-containing particles, but not -synuclein fibrils, LRRK2 hMG trigger DAn degeneration, in a process that is prevented by pre-treatment with the immunomodulatory drug ivermectin. Finally, post-mortem analysis of midbrain tissue of LRRK2-PD patients show increased microglia activation around NM-containing neurons, confirming our in vitro findings. Overall, our work highlights NM-activated microglias role in PD progression, and provides a model for testing therapeutic targets.

cell biology↗

Lost in HELLS: disentangling the mystery of SALNR existence in senescence cellular models

Long non-coding RNAs (lncRNAs) have emerged as key regulators of cellular senescence by transcriptionally and post-transcriptionally modulating the expression of many important genes involved in senescence-associated pathways and processes. Among the different lncRNAs associated to senescence, Senescence Associated Long Non-coding RNA (SALNR) was found to be down-regulated in different cellular models of senescence. Since its release in 2015, SALNR has not been annotated in any database or public repository, and no other experimental data have been published. The SALNR sequence is located on the long arm of chromosome 10, at band 10q23.33, and it overlaps the 3 end of the HELLS gene. This investigation helped to unravel the mystery of the existence of SALNR by analyzing publicly available short- and long-read RNA sequencing data sets and RT-PCR analysis in human tissues and cell lines. Additionally, the expression of HELLS has been studied in cellular models of replicative senescence, both in silico and in vitro. Our findings, while strongly questioning the actual existence of SALNR as an independent transcript, support the expression of a predicted HELLS isoform entirely covering the SALNR genomic region. Furthermore, we observed a strong down-regulation of HELLS in senescent cells versus proliferating cells, supporting its role in the senescence and aging process. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=106 SRC="FIGDIR/small/526712v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@1178eb8org.highwire.dtl.DTLVardef@19ae822org.highwire.dtl.DTLVardef@fe1c49org.highwire.dtl.DTLVardef@f31ae1_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Metrics of Coral Microfragment Viability

Coral reefs are being degraded at unprecedented rates and decisive intervention actions are urgently needed to help them. One such intervention in aid of reefs is coral cryopreservation. Although the cryopreservation of coral sperm and larvae has been achieved, preservation of coral fragments including both its tissue and skeleton, has not. The goal of this paper was to understand and assess the physiological stressors that might underlie coral fragment cryopreservation and the long-term consequences of these physiological exposures to continued growth. Therefore, we assessed small fragments ([~]0.5 x0.5 mm2) from the Hawaiian coral, Porites compressa, examining: 1) the sensitivity of the fragments and their algal symbionts to chilling temperatures; 2) the sensitivity of the coral to complex cryoprotectants; 3) methods to safely remove the algal symbionts from the coral fragment for cryopreservation, given the two symbiotic partners may require different cryopreservation protocols; 4) continued growth over time of coral fragments once returned to running seawater after treatment exposures; and, 5) assessment of health and viability of microfragments after treatments examining the distribution of green fluorescent protein and fluorescent symbionts. Technological advances in cryo-technology promise to support successful coral fragment cryopreservation soon, and its success could help secure much of the genetic and biodiversity of reefs in the next decade.

cell biology↗

Immunosuppressive tocilizumab prevents astrocyte induced neurotoxicity in hiPSC-LRRK2 Parkinson's disease by targeting receptor interleukin-6

Parkinsons disease (PD) is associated with premature death of dopamine-producing neurons in the brain. Previous studies have shown that astrocytes of PD patients may contribute to neuronal degeneration by mechanisms involving both direct cell-to-cell contact and transfer of soluble molecules. Since it has been proposed that PD patients exhibit an overall pro-inflammatory state, and since astrocytes are key mediators of the inflammation response in the brain, here we sought to address whether astrocyte-mediated inflammatory signaling could contribute to PD neuropathology. For this purpose, we generated astrocytes from induced pluripotent stem cells (iPSCs) representing PD patients and healthy controls. Transcriptomic analyses identified a unique inflammatory gene expression signature in PD astrocytes compared to controls. In particular, the pro-inflammatory cytokine IL-6 was found to be highly expressed and released by PD astrocytes, and to induce toxicity in dopamine neurons. Mechanistically, neuronal cell death was mediated by IL-6 signaling via IL-6 receptor (IL-6R) expressed in human PD neurons, leading to downstream activation of STAT3. Importantly, astrocyte-induced cell death in PD disease midbrain neurons could be prevented by blocking IL6R-mediated signaling using clinically available antibodies. Moreover, examination of postmortem tissue brain of early-stage PD patients uncovered increased numbers of dopamine neurons overexpressing IL-6R and of reactive astrocytes overexpressing IL-6, compared to healthy brains. Our findings highlight the potential role of astrocyte-mediated inflammatory signaling in neuronal loss in PD, and open the way for new therapies based on IL-6 immunomodulation for preventing PD pathogenesis.

neuroscience↗

iPSC-based modeling of THD recapitulates disease phenotypes and reveals neuronal malformation

Tyrosine hydroxylase deficiency (THD) is a rare genetic disorder leading to dopaminergic depletion and early-onset parkinsonism. Affected children present with either a severe form that does not respond to L-Dopa treatment (THD-B), or a milder L-Dopa responsive form (THD-A). We generated induced pluripotent stem cells (iPSCs) from THD patients that were differentiated into dopaminergic neurons (DAn) and compared with control-DAn from healthy individuals and gene-corrected isogenic controls. Consistent with patients, THD iPSC-DAn displayed lower levels of DA metabolites and reduced TH expression, when compared to controls. Moreover, THD iPSC-DAn showed abnormal morphology, including reduced total neurite length and either an abnormal TH proximodistal gradient (THDA), or neurite arborization defects (THDB). Treatment of THD-iPSC-DAn with L-Dopa rescued the neuronal defects and disease phenotype only in THDA-DAn. Interestingly, L-Dopa treatment at the stage of neuronal precursors could prevent the alterations in THDB-iPSC-DAn, thus suggesting the existence of a critical developmental window in THD. Our iPSC-based model recapitulates THD disease phenotypes and response to treatment, representing a promising tool for investigating pathogenic mechanisms, drug screening, and personalized management.

neuroscience↗